This was a collaborative study with the University of British Columbia to evaluate the effects of this novel nicotinic agonist in early Parkinson's disease by administering the drug to patients who were given half their usual dose of L-dopa. The principal goal was to see if SIB-1508Y could augment the effects of 1/2 of the usual dose of L-dopa. A total of 10 patients were studied at this site. Outcome Measures: Motor assessments were performed pre-dose and 0.5, 1, 2, 2.5, 4, 6, and 8 hours post dose. The motor function tests consisted of the motor component of the Unified Parkinson's Disease Rating Scale (UPDRS); the Purdue pegboard test; the walking test; and the dyskinesia scale. Eighteen (18) subjects performed the motor assessments for all 4 treatments: 8 from The University of British Columbia and 10 from the University of Vermont. Ten (10) subjects from our center (The University of Vermont) were evaluated for cognitive and behavioral assessments in addition to the motor changes. Cognitive assessments were performed 3 hours after each dose of study drug and consisted of the Critical Clicker Fusion test; Category Generation, Stroop Task, Divided Attention task; Repeated Acquisition Task; and the Buschke Selective Reminding Task. The behavioral or mood/vigilance assessments were performed before and 3 hours after study drug administration. The behavioral assessments consisted of the Profile of Mood States (POMS); Subjective Visual Analog Inventory; Objective Visual Analog Inventory; Stanford Sleepiness Scale, Physical Symptoms; and the Brief Psychiatric Rating Scale for Behavioral Assessment. Statistical Methods: An analysis of variance was conducted along with analysis of repeated measures, comparing doses across time. Center, day (order), and baseline value were included in the model and analyzed as covariants.